Allergic diseases are commonly treated by drug therapy with an antihistamine, antiallergic, steroid or the like. Recently, however, in light of the limits of drug therapy and from the viewpoint of preventive medicine, lactic acid bacteria affecting gut immunity have attracted attention for their effectiveness in the prevention and treatment of allergic diseases (Patent documents 1 to 3). Gut immunity is an immune mechanism for elimination of pathogenic microorganisms that have been orally ingested, and it is the current opinion that suppression of overresponse of the gut immunity is useful in the prevention and treatment of allergic diseases.
For example, it has been reported that some strains of Bifidobacterium infantis, Bifidobacterium breve, Bifidobacterium longum and Bifidobacterium bifidum are effective in the treatment of food allergy (Patent document 1). Also, it has been reported that some strains of Enterococcus faecalis, Lactobacillus reuteri (Patent document 2), Lactobacillus paracasei, Lactobacillus plantarum and Streptococcus salivarius (Patent document 3) are effective against bronchial asthma, allergic rhinitis and atopic dermatitis.
Further, it is known that allergic diseases correlate with physical and psychological stress, and that individuals with higher stress levels exhibit worse symptoms (Non-patent document 1). It is therefore believed that not only suppression of the immune response of the body but also elimination of daily stress is required to prevent and treat allergic diseases.
Patent document 1: Japanese Patent Application Laid-Open No. 10-309178
Patent document 2: Japanese Patent Application Laid-Open No. 2000-95697
Patent document 3: Japanese Patent Application Laid-Open No. 2005-139160
Non-patent document 1: Satoshi Ogino, “Stress and Allergic Diseases: Focus on Preparatory School Students”, Jibiinkoka Tenbo (Oto-rhino-laryngology, Tokyo), 2002, Vol. 45, p. 204-210